Deerhunter4

I have a tune and went down to 0.030. Truck runs better now. Idle is smooth and no shuddering at all.

57hippie

I have a tune and had some shuddering in 3rd when I hammer it re gap down to .030 no shuddering and truck runs so much better. My spark plug gap was 4 0f them was .045 and 2 .042.

begone

Just bought NGK LTR7IX-11, getting shipped from Amazon (pretty cheap there) - I'll let you know what I find when I pull my plugs and reinstall. Haven't have any issues on shuddering, but I just want to take care of the truck. Maybe it will increase the performance as well.

It's a 2011 F150 Ecoboost with Injen Intake and 5* Tune - I've had it since August of 2011 and it has 29k miles on it.

MadocHandyman

That's really excessive! Did you have the 50-60 mph shudder or the loss of power when floored issue?

MadocHandyman

I've wondered if this has been an issue, combined with excessive moisture in the IC.
Is it possible that some of the ones reporting the loss of power and severe misfire, maybe has just one or two plugs way off spec and those cylinders are being snuffed out?

57hippie

I had the loss of power 1 time before. Had some 50-60 mph shudder but none now.

boosted150

Just checked all my plugs.

I have to say, this was not an "easy" job. Now I know there are much harder engines to work on, maybe I've been spoiled in the past. But, in order to get at all the plugs I had to contort myself and get waist deep in the engine compartment... ok maybe not waist deep, but you get the idea. Once you get the cover off and breather hose out of the way, it wasn't too bad.

Truck has a build date of June 2011. All 6 plugs were dead on 0.035, and all looked like they were burning evenly, no excessive carbon buildup anywhere. 12,000 miles on the Odometer.

Was it worth it? Hard to say, but now I know they're all at 0.035, AND they are all anti-seized to prevent the gratuitous use of expletives in the future.

CoreyMS

I imagine the spark blowout could happen >.40, especially tuned with any extra boost. For most I think the .30 is a little low, if you have a pretty conservative tune. The more boost the more it's needed. I've been experimenting...I had .30 on the stocks and was fine and am working my way up. Honestly I ran serveral other tunes before I ever messed with the plugs and never had a issue, mine were all just under .35 from the factory. .35 feeler wouldn't go but a .32 did with a little slack.

engineermike

This has been my theory for a while now. Lots of turbo cars with intercoolers aren't reporting this condensation issue. Could it be that a stronger ignition system and/or narrower gap has been masking this issue for 25+ years?

alpo

Quite possibly. I've heard many stories of forced induction blowing the spark out if the gap is too wide.

I'd start conservatively, then work up as required. Try the maximum recommended pressure and see how the engine responds.